Forming and filling tubes for package making apparatus



July 1, 1958 J. DREEBEN 2,840,966

FoRMING AND FILLING TUBES FOR PACKAGE MAKING APPARATUS Filed Aug. 1, 1956 INVENTOR @TM i? ATTORNEY United States atent O FORMING AND FILLING TUBES FOR PACKAGE MAKING APPARATUS Jack Dreeben, Philadelphia, Pa. Application August 1, 1956', Serial No. 601,529 3 Claims. (Cl. 53-177) This invention relates to forming and lling tubes for package making apparatus.

It has heretofore been proposed to draw transparent synthetic plastic sheet material from a web roll, form the web about a tube into a bag or envelope with a longitudinal sealalong the web, lill the bag or envelope through the tube, seal the top of one package withsimultaneous sealing of the bottom of the succeeding package, and sever the seal intermediate its top and bottom edges to separate the packages, this all 'being effected in a timed sequence.

One of the materials heretofore commonly employed has been regenerated cellulose in sheet form, available as cellophane, and this has a very low elongation rate.

The forming tubes heretofore available, and particularly the exterior forming shoes employed therewith, were suitable for sheet material of low elongation rate.

Upon attempting to form packages in a similar manner for polyethylene, with the forming tubes and shoes previously used, considerable diiculty has been encountered because of the high elongation rate which for polyethylene up to ve mils (0.005 inch) in thickness is of the order of 300 to 800% with recoil approximately 65%.

Because of the elongation characteristics of the polyethylene the forming tubes, and particularly forming shoes heretofore available, have not functioned satisfactorily.

It is the principal object of the present invention, therefore, to provide an improved character of forming tube for use with sheet material of high elongation rate in a package forming machine.

It is a further object of the present invention to provide a simple but effective attachment for package forming machines by which high elongation rate sheet material from the web roll can be formed into a tube for longitudinal sealing and other operations.

It is a further object of the present invention to provide, for package forming and lling machines, a simple but elfective forming and filling tube construction.

Other objects and advantageous features of the invention will be apparent from the description and claims.

The nature and characteristic features of the invention will be more vreadily understood from the following description taken in connection with the accompanying drawings forming part thereof, in which:

Figure l is a view in perspective `of a filling and forming tube in accordance with the present invention removed from the packaging machine;

Fig. 2 is a side elevational view of the lling and forming tube;

Fig. 3 is a rear elevational view of the iilling and forming tube; and

Fig. 4 is a horizontal sectional view taken approximately on the line 4-4 of Fig. 2.

It should, of course, be understood that the description and drawings herein are illustrative merely, and that various modifications and changes can be made in the structure disclosed without departing from the spirit f the invention.

vginal edges overlapped.

Like numerals refer to like parts throughout the several views.

Referring now more particularly to the drawings, the forming and filling tube in accordance with the invention includes a circular cylindrical tube 10 with a mounting bracket arm 11 secured thereto in any desired manner. The ann 11 is adapted to be suitable supported in the frame of the package making machine, being fastened to a mounting block 12.

Spaced below the arm 11, a split shoe 13 is provided having an upper section 13a and a lower section 13b with an open slot 13e therebetween. The upper section 13a is provided with overlapping end portions 14 and 15. The shoe 13 is supported by a mounting bracket arm 16 which is preferably connected to the lower section 13b and also fastened to the mounting block 12 to hold the shoe 13 in predetermined relation to the tube 10. The shoe 13 surrounds the tube 10 in spaced relation thereto (see Fig. 4) to provide clearance for the web and the end portions 14 and 15 are in spaced relation to the tube 10 an-d to each other to provide clearance for the web.

The top margin of the shoe 13 is of particular shape and relatively flat with respect to the horizontal, and includes an elevated part 17 with downwardly sloping parts 18 on each side, with upturned ends 19 extending, slightly above the sloping part 18.

It will be noted that the highest and lowest parts of the top margin of the shoe 13 are at diametrically opposed parts of the tube 10. The difference in eleva# tion between the highest and lowest parts of the top margin of the shoe 13 has been found to be of particular importance and is of the order of one fourth to one sixth of the diameter of the tube 10. With differences in heights beyond this range excessive stretch of the elongatable web, or binding of the web, or both, occur and a smooth sliding action for forming the web into a tube is difficult to achieve.

It has also been found that the forming tube of the present invention works advantageously with feed mecha-l nism as shown in my copending application tiled .luly 20, 1956, Serial No. 599,204.

ln use, a web of sheet material to be formed into a tube for package making is delivered in'flat condition from a web roll and is delivered over the top marginal edge of the shoe and downwardly around the tube 10 for forming the web into cylindrical shape with the marri`he web in passing over the top margin of the shoe 13 engages the elevated part 17, the downwardly sloping parts 18 on each side with the margins guided by the upturned ends 19 and accommodated by the spaces between the end portions 14 and 15 and between the end portion 15 and the tube 10. As the web moves downwardly its edges are maintained crossed and guided so as to be straight in their overlapped downward movement, The web edges thus maintain l themselves in their proper position.

The hollow tubular web, as thus formed, is ready for longitudinal sealing in any desired manner, can have transverse seals applied thereto, the materials to be packaged being delivered in quantities measured as to weight, volume or number, as desired, through the interior o-f the tube 10 and above a transverse seal in a well known manner I claim:

l, A web former for package making machines in which the longitudinal margins of an elongated strip of sheet material having a high elongation rate are brought together in overlapped relation for longitudinal sealing comprising a vertical abutment member for engagement by an inner of said margins, an upright shoe of round shape surrounding said abutment member and having inner and outer end portions in overlapping and spaced relation and the inner end portion in spaced relation to said abutment, said shoe having a top marginal strip engaging and guiding edge, said edge having diametrically oppositely v disposed uppermost and lowermost web guiding edge portions With the top marginal edge at said overlapped positions being upturned.

2. A web former for package making machines in which the longitudinal margins of an elongated strip of sheet material having a high elongation rate are brought together in overlapped relation for longitudinal sealing coinprisiug a vertical abutment member for engagement by an inner of said margins, an upright shoe of round shape surrounding said abutment member and having inner and outer end portions in overlapping and spaced relation and the inner end portion in spaced relation to said abutment, said shoe having a predetermined interior transverse diameter through said overlapping end portions, said shoe having a top marginal strip engaging and guiding edge, said edge having diametrically ppositely disposed uppermost and lowermost web guiding edge portions, the vertical distance between said last mentioned web guiding edge portions being less than one fourth to one sixth of the said diameter.

3. A web former for package making machines in which the longitudinal margins of an elongated strip of sheet .4 material having a high elongation rate are brought together in overlapped relation for longitudinal sealing comprising a vertical abutment member for engagement by an inner of said margins, an upright shoe of round shape surrounding said abutment member in spaced relation thereto and having inner and outer end portions in overlapping and spaced relation and the inner end portion in spaced relation to said abutment, said shoe having a predetermined interior transverse diameter through said overlapping end portions, said shoe having a top marginal strip engaging and guiding edge, said edge having diametrically oppositely disposed uppermost and lowermost web guiding edge portions with the top marginal edge at said overlapped portions being upturned, the vertical distance between said last mentioned web guiding edge portions being less. than one fourth to one sixth of the said diameter.

References Cited in the le of this patent UNITED STATES PATENTS 1,986,422. Zwoyer Ian. 1, 1935 2,257,433 Stokes Sept. 30, 1941 2,641,881 Donofrio June 16, 1953 2,679,195 Whytlaw May 25, 1954 

